Research evaluates PAWS system on welfare of laying hens
A novel lighting source, Pulsed Alternating Wavelength System (PAWS), is being introduced to the industry and delivers light through a specific pattern of alternating wavelengths in nanosecond pulses.
Laying hens require correct lighting for proper development and reproduction. However, there is limited research on the effects that different types of light have on the welfare and skeletal quality of the bird. A novel lighting source, Pulsed Alternating Wavelength System (PAWS), is being introduced to the industry and delivers light through a specific pattern of alternating wavelengths in nanosecond pulses. This lighting system may improve the growth rate of birds, decrease the age at first egg, and decrease aggressiveness and nervousness behaviors. However, there are no published studies on how PAWS affects production and the welfare of poultry. Increasing growth and decreasing age at first egg through the lighting source would be economically beneficial to laying hen producers. However, the unknown subsequent effect on the skeleton may have negative impacts on the bird, especially later in life when layers are more susceptible to keel bone fractures. Understanding the effects that PAWS has on the hen's welfare, physiology and skeleton are critical if this technology is to be used widely in the industry. A bone quality assessment method that has not been utilized in poultry, called reference point indentation (RPI) is also being tested. The project objective was to evaluate the effects of Pulsed Alternating Wavelength System (PAWS) on the welfare and skeletal quality of laying hens utilizing traditional bone quality assessment methods and RPI.
In the study, there were two PAWS flocks (PAWS1 and PAWS2) and a control flock used that were housed in conventional cages at a commercial facility. The physiological welfare of the hens was improved by PAWS lighting at the younger ages (22 and 32 weeks of age) as based on the reduced serotonin turnover ratios that the PAWS1 flock had compared to the control. There were more variable differences in the older ages (50 and 52 weeks of age), but overall, the older ages had much lower serotonin turnover ratios compared to the younger ages regardless of treatment. While the physical welfare results were more inconsistent, PAWS2 generally had decreased welfare quality scores across most parameters, especially feather coverage scores, while PAWS1 fluctuated more. However, PAWS2 did have reduced keel tip fractures at the post-peak production phases (50 and 52 weeks of age). When analyzing bone quality parameters between the peak (32 weeks of age) and post-peak (52 weeks of age) production phases, the control flock had decreased fracture force in the post-peak phase compared to the peak phase. The fracture force of PAWS1 flock remained constant between the phases. There were no treatment differences in bone ash percentage, but bone ash did decrease between the peak and post-peak production phases. When analyzing bone quality parameters between all three flocks at the peak production phase, digital bone mineral content (BMC) tended to be higher in PAWS2 compared to the control. The RPI outputs were lower in PAWS2 compared to PAWS1 and the control, which indicates superior bone quality. The fracture force was not different between treatments.Overall, PAWS lighting appears to improve both physiological and physical welfare as well as most bone quality parameters.
Short-range benefits for the laying hen industry include that PAWS lighting does not seem to have a detrimental effect on the welfare or bone quality of birds. Findings indicate that the industry can start implementing these lights without worry of harming the hens. Long-range benefits could include improved bone quality and welfare, which may lead to increased longevity and productivity of hens. Implementing these lights in cage-free production may aid in decreasing keel bone damage. However, much more research is required to delve into any potential benefits before there is industry-wide change.
Laying hens require correct lighting for proper development and reproduction. However, there is limited research on the effects that different types of light have on the welfare and skeletal quality of the bird. A novel lighting source, Pulsed Alternating Wavelength System (PAWS), is being introduced to the industry and delivers light through a specific pattern of alternating wavelengths in nanosecond pulses. This lighting system may improve the growth rate of birds, decrease the age at first egg, and decrease aggressiveness and nervousness behaviors. Dr. Darrin M. Karcher and Brittney Emmert of Purdue University recently completed a research project with an objective of evaluating the effects of PAWS on the welfare and skeletal quality of laying hens utilizing traditional bone quality assessment methods and reference point indentation (RPI). View our interview.
